Improvement in drawing-boards



CHARLES G. COLLINS.

Improvement in Drawing-Boards. N0.127,573. Patentedlune 4,-1872.

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UNITED STATES PATENT QFFIGE.

CHARLES Gr. COLLINS, OF NEW YORK, N. Y.

Y IMPROVEMENT IN DRAWING-BOARDS.

Specification forming part of Letters Patent No.127,573, dated J one 4, 1872.

Specification describing an Improvement in Drawing-Boards, invented by CHARLES G. COLLINS, of the city, county, and State of New York.

The object of this invention is'to prevent the splitting of the longitudinal portion or sections of a drawing-board, in shrinking transversely to the transverse end pieces or battens, which are used to secure the longitudinal'portion or sections against warping. To this end it consists in the combination, with the said longitudinal portion or sections, and with the end pieces or battens fitted to the former by tongues and grooves, of slots or cavities in the said end pieces, bridge-plates arranged over the said slots, and screws passing through the latter and through the said slots and screwing into the ends of the said longitudinal portion or sections, whereby the shrinkage of the latter is provided for without their splitting.

In the accompanying drawing, Figure l is a part] y-sectional face view of a board constructed according to my invention. Fig. 2 is an edge view of the same; and Fig. 3 is a transverse section thereof.

Similar letters of reference indicate corresponding parts in all the figures.

A is the longitudinal portion or body of the board, composed of a single longitudinal piece, or two or more of such pieces glued together. B B are the end pieces or battens. These latter are fitted to the side ends or edges of the former by tongues and grooves, and are seproject beyond them, and they bear on the plates D D, and are thereby prevented from indenting themselves into the wood and so becoming fixed in one position.

As the sections A A shrink the screws slide along in the recesses and slots in the battens, and, by moving with them, instead of holding the contiguous parts of the sections rigid, prevent said sections from splitting.

Claim.

The combination, with the longitudinal portion or sections A A of the body of the board, and with the end pieces or battens B B ton gued and grooved thereto, of the slots ff, the screws 0 (J, and the plates D D, the whole arranged substantially as and for the purpose herein specified.

CHARLES G. COLLINS.

Witnesses:

FRED. HAYNES, R. E. RABEAU. 

